Thermostatic valve



lume 9 VV. ROBERTSHAW THERMOSTATIC VALVE Filed Jan. 29,

4' 20 hll i m YV W Q WIM.

Patented June 22, 1926.

FREDERICK W. ROBERTSHAW, OF PITTSBURGH, PENNSYLVANIA.

THERMOSTATIC VALVE.

Application led January 29, 1924. Serial' No. 689,308.

The present invention relates broadly to hot Water heating systems and thermostatic valves therefor, and more particularly to valves of the character adapted for use with boilers ofthe hot. Water storage vtype for controlling the supply of combustible fluid to a burner, although the utility of the invention in this respect is not limited.

At the present time. there is a growing tendency toward the use of hot Water storage tanks having a circulating connection leading from a lower portion of the tank to a heater, and thence to an opening in one side of the tank. The present invention is especially adapted to a circulating conneetion of this character.

By the present invention there is provided an improved arrangement enabling the maintenance of uniform temperature con` ditions in the boiler at all times.

Another object of my invention is to provide an improved form of valve adapted for use in this connection. the valve being provided preferably with normally sealed means whereby the temperature at which the valve operates to completely cut off the flow of gas. or operates to establish gas flow, may be easily adjusted, the sealing of said means preventing the valve from accident or molestation.

In the accompanying drawings there is shown, for purposes of illustration only, a preferred embodiment of the present invention, it being understood that the drawings do not define the limits of my invention, as changes majY be made in the construction and operation therein disclosed Without departing from the spirit of the invention or scope of my broader claims.

In the drawings- Figure 1 is a side elevation of a portion of a hot Water heating system and its connections, including my improved thermostatio valve;

Figure 2 is a detail vieuon an enlarged scale of a portion of the valve;

Figure 3 is a vertical longitudinal sectional view through the construction illustrated in Figure 2, certain of the parts being broken away and certain of the parts shown in elevation; and

Figure 4 is a detail view on an enlarged scale of a portion ofthe valve.

In accordance with the present invention there may be provided a hot water boiler' 2 of the storage type having an inlet 3 for cold )vater and an outlet 4 for hot Water. Leading' from a point adjacent thejbottom ot the tank there 1s a circulating connection 5 supplying Water to be heated to a heat-ery (i, which heater may be of any usual and well known construction. After passing through the heater the Water is adapted to be conducted Vto the boiler. This circulation is established by means of a connection For controlling the minimum supply of gas to the burner to prevent extinguishment thereof, there may be provided a by-pass 15 controlled by an adjustable needle valve 16. In order to seal this needle valve, and to prevent tampering therewith, there may be provided a cap 17.

The valve body 8 has projecting from the rear thereof a tubular Water connection 18 having an inlet 19 adapted to cooperate With the circulating connection 7 and an outlet 2O threaded to receive a nipple 7 which is threaded at its opposite end into the side of the boiler. By reason of this construction it will be apparent that hot Water leaving the heater 6 passes through the connection 18 before entering the boiler. Extending through the connection 18 and the nipple 7 and projecting into the boiler is an expansible tube 21 Within Which is mounted a relatively non-expansible member 21. These relatively expansible and non-eXpansible members constitute a thermostatie control by means of which the valve disk 11 is operated as will be hereinafter more fully described. As the members are not only subjected to the hot Water leaving the heater but to the temperature of the Water Within the boiler. it Will be apparent that the operation of the valve is more nearly stabilized and intermittent rapid opening and closing movements thereof are prevented.

The valve disk has projecting from opposite sides thereof tubular stems 22 and 23. The stem 23 may be guided Within the outer 'a central opening adapted to guide the stem as described and surrountiling the opening is a recess 25 within which is mounted a felt Washer 26 and a metallic Washer 27. Abutting at one end against this metallic washer `and at its opposite end against the valve disk 11 is a compression spring 28. It will be apparent that this spring not only serves to normally urge the valve in one direction, but also serves to compress the packing washer 26, whereby the interior of the valve body is effectively sealed against the escape of gas around the stem 22.

For transmitting operating pressure from the thermostat to the valve disk l1 in opposition to the action of the spring 28 there is provided a packing pin 29 extending through the tubular guide ystems on the valve. At one end, the packing pin is in engagement with the relatively non-expansible member 2l', while at its opposite end it is vin engagement with an adjusting screw 30. This adjusting screwis threaded through the end of the tubular stem 22 and is' held in adjusted position therein by a binder set screw 31.y This binder set screw projects at its outer end into a slot 32 formed in the externally threaded projection 33 on the valve cap. With this construction, by loosening the binder set screw, the adjusting screw 30 may be threaded inwardly or outwardly as required. If threaded outwardly, it will be apparent that the packing pin is urged toward the relatively non-expansible member 21 whereby contraction of the relatively expansible casing 21 will open the valve at an earlier stage than would be the case if the packing pin were moved in the opposite d1,- rection. In this manner the temperatures at which the valve disk is opened or closed may be accurately controlled. During such adjustment of the adjusting screw, rotation of the valve disk with the adjusting screw is prevented by reason of the projection of the outer end of the adjusting set screw 31 into the slot 32. This adjusting mechanism for the valve may be protected and -the interior of the valve further sealed against the escape of gas by a cap 34. It will be understood that the caps 17 and 34 have their inner ends machined to cooperate with machined surfaces on the valve body, whereby tight fits are insured/ If desired, the end of the stem 22 may be extended as indicated at 22. This extension, where provided, will preferably be a polygonal cross section whereby in the event of loss of the binder set screw the end of the stem may be easily held to permit adjustment of the screw 30 as will be clearly understood.

I have found that the provision of a relatively short path of circulation, suchA as is insured where the circulating connection communicates with' the side of the storage tank enables a uniform temperature to be maintained due to the more rapid movement of the Water through the cycle. lith a valve construction as set forth, such a connection with the side of the storage tank is facilitated and the usc of at least one lifting is obviated.

The advantages of the present invention arise from the provision ofV an improved valve adapted to be easily controlled to adjust the temperatures at which it is operated.

Further advantages arise from the construction of the valve body whereby in the use thereof the thermostat may be partially subjected to the temperature of the water leaving the heater and partially subjected to the temperature of the water within the boiler.

I claim:

1A In a thermostatic valve, a valve body Ihaving inlet and outlet openings, a valve controlling communication between said openings, a tubular stem projecting from opposite sides of said valve, means for guiding said stem, thermostatic means for operating the valve, and a packing pin slidably mounted in said tubular stem, said packing pin co-operating with said stem at one end and with said thermostatic means at its opposite end, substantially as described.

2. In a thermostatic valve, a valve body having inlet and outlet openings, a valve controlling openings, astem projecting from opposite sides of said valve, means for guiding each end of said stem, thermostatic means for operating said valve, and means co-operating with the end of the stem remote from the thermostatic means for adjustably controlling the operation of the valve, said last mentioned stem end projecting beyond said body to enable the same to be engaged and held during adjustment, substantially as described.

3. In a thermostatic valve, a valve body having inlet and outlet openings, a valve controlling communication between said openings, a tubular stem projecting from said valve, means for guiding said stem, tnermostatic means for operating the valve, a packing pin slidably extending through said stem and engaging said thermostatic means at one end, and adjustable means establishing operative engagement between the opposite end of said pin and said stem, substantially as described.

4. In a thermostatic valve, a valve body having inlet and outlet openings, a valve controlling communication between said openings, a hollow stem projecting from said lli Htl

communication between said valve, means for guiding said stem, thermostatic means for operating the valve, a packing surrounding said stem, means normally urging the valve in one direction in opposition to the thermostatic means and forcing said packing into engagement with said stem, a closure for one end of said stem,`and v 4'adjustable means for said valve adapted to be exposed by removal of said closure, one end of said stem projecting into said closure to permit the same to be engaged and held when the closure is removed, substantially as described.

5. In a thermostatic valve, a valve body having inlet and outlet openings, a valve controlling communication between said openings, a stem projecting from said valve, means for guiding said stem, a thermostatic means for operating the valve, adjustable means establishing engagement between said valve and said thermostatic means, and

means preventlng rotation of said valve dur.

ing the adjustment thereof, said last mentioned means being effective for maintaining the adjustable means in adjusted position,

, substantially as described.

6. In a thermostatic valve, a valve body having inlet and outlet openings, a valve controlling communication between said openings, thermostatic means for operating said valve .and means forsubjecting different portions of. said thermostatic means to water at diii'erent temperatures, substantially as described.

7 In a thermostatic valve, a valve body having inlet and outlet openings, a valve controlling communication between said openings, said valve having an opening therethrough, a. pin slidably projecting through said opening, thermostatic means detachably engaging one end of said pin, adjustable means engaging the opposite end of the pin and forming an operative connection between said opposite end of said pin and said valve, and means for preventing rotation of said valve 'during the adjustment thereof, substantially as described.

8. In a thermostatie valve, a valve body having inlet and outlet openings, a valve controlling communication between said openings, said valve having an opening therethrough, a pin slidably projecting through said opening, thermostatic means detachably engaging one end of said pin, and adjustable means engaging the opposite end of said pin and forming an operative connection bet-Ween the pin and said valve, substantially as described.

9. In a thermostatic valve, a valve body having `inlet and outlet openings, a valve controlling communication between said openings, said valve having an opening therethrough, a packing pin slidably projecting through said opening, thermostatic means engaging one end of said pin, and means engaging said pin for moving the same axially through said valve, substantially as described.

10. In a thermostatic valve, a valve body having inlet and outlet openings, a valve controlling communication between said openings, a tubular stem projecting from said valve, means for guiding said stem, thermostatic meansfor operating the valve, a pin slidably mounted in said stem and engaging said thermostatic means at one end, and a screw adjustably engaging said stem and said pin for effecting adjustment of said valve, substantially as described.

1l. In a thermostatic valve, a valve body having inlet and outlet openings, a valve controlling communication between said openings, said valve having a hollow stem projectin from opposite sides thereof, a pin slida 1y mounted in said stem, an adjusting screw engaging one end of said. pin. said stem on one end thereof being shaped to permit holding the valve against rotation while the screw is adjusted, and a closure adapted upon removal to expose said screw, substantially as described.

12. 'In a thermostatic valve, a valve body havin inlet and outlet openings, a valve contro ing communication between said openings, said Valve having a guiding stenl of angular cross section at one end thereof, a cap adapted to provide access to said stem, a pin within said stern, and adjustlng means cooperating with said pin and adapted to be adjusted upon removal of said cap, substantially as described.

In testimony whereof I have hereunto set my hand. A

FREDERICK W. ROBERTSHAVV. 

